I finished my First Bike/Hub Motor Conversion. scooterman101

[ScooterMan101]

Well I finished it a couple of months ago, except for a clean looking battery enclosure. ( the battery is one of those Generic Chinese Batteries that fit in e-bikes that have a space between the seat post and rear tire in which to just slide in and out the battery pack ) I took the battery out of the case in order to fit into the Lux , Woman's Bike Frame.

I have 6 rides on it as of now and I am very happy with the build, and choice of Hub motor/its power.

First I will talk about the bike I chose for the build, since this thread is to both to show the long term experienced DIY builders/authors that I took the advice that many of you have thankfully contributed , and learned from your mistakes.
and to also perhaps guide the newcomers .

Then further down I will talk about the motor/wheel build/controller/battery pack, then later some performance data . ( only 6 rides so far )


For the Bike I chose the 2014 Diamondback Lux 27.5 women's mountain bike for several reasons ( the 2015 is the same exact bike ).

1) I did not find a good priced, used, full suspension bike fast enough .
2) The Lux has very good/thick dropouts, in which to bolt the big axle/nuts of the hub motor to .
3) The Lux has good standover height , which is important for dismounting when you have panniers/items on top of a rear rack, and dismounting at anytime.
4) The Lux is a 27.5 inch ( 650b ) wheel bike, so it will be current for a long time to come.
5) With the 27.5 inch wheels and wide 54 mm road/touring tires I put on , it has almost the same outer tire diameter as a road bike, so I can really roll down the road.
6 ) It is priced very good, $ 600 , however it often goes on sale for $ 500 plus tax.
7) At apx $ 550 you have money for component upgrades/changes, or you can keep it stock.
It is a 8 speed bike, and with most hub motors that have a freewheel hub body, not a Cassette Freehub Body, 8/9 speed Freewheel Cogs are the largest set of cogs even with spacers without over stretching the rear dropout/rear frame of a bike.

[ScooterMan101]

Here are a couple of pictures.

[beast775]

Great first build,did you make a battery holder bracket from the frame tube bottle holder? just wondering because velcro and zap straps dont hold much.

[ScooterMan101]

The battery case is plexiglass that was left over excess from a Plastic Mgf business, what I did was drill two holes in the bottom, the same spacing as the two bolt holes in the frame , where you would bolt your bottle cage onto, then I used angled head screws so as to have the least amount of screw head in the case, camfored the plastic a little to set the screw heads down a little more into the plexiglass , then put dense foam between the case/screw heads and battery.

The velcro strap and zip ties are just there as a back up.

[ScooterMan101]

It is a good thing I spent only $ 550 on the bike because I did so many changes and improvements that I spent more than that by far just on the changes .

First thing I changed was the Bottom Bracket, when I got the bike and took off the chain , I noticed allot of friction in the Bottom Bracket, it was one like you see on cheep big box store bikes.
I ordered the Shimano BB UN 55 , and that made a huge improvement. not the same as the very efficient BB30 bearings that you see on high end road bikes, but about as close as you can get with a cartridge BB.

[ScooterMan101]

Next I looked for a good 8 speed freewheel,
at first I ordered the Sunrace 9 speed freewheel that is made for electric bikes, ( an improvement on regular freewheels)
but decided on the Sunrace 8 speed freewheel , that way I did not have to stretch out the rear dropout spacing more than I already had to.

I looked at cheep 8 speed freewheels at some bike shops , but they did not freewheel as good/efficent as the Sunrace 9 speed freewheel made for e-bikes, I then found the 8 speed freewheel version, also made by Sunrace. It freewheels better than others I tested by hand at a few bike shops.

[ScooterMan101]

Notice that the Sunrace 8 speed freewheel that is better quality is 13-32 tooth.

When I bought the electric hub motor/controller/battery from Todd at Electricmotorsports, he said I only need a 7 speed freewheel because most people only use a 11 tooth cog since there is so much assist from the electric motor, I still wanted 8 or 9 speeds so as to work better with a 8 or 9 speed shifter , and , Legs/Knees when going up any amount of incline . so ... because the Sunrace is 13 tooth at the smallest cog, I decided to get rid of the mountain crankset that was 44 tooth on the outer chainring , and buy a 8 speed/chain Road Bike Crankset that has 50 teeth on the outer chainring. I am very happy with that setup, in fact , I ride 99% of the time , only on the 50 tooth outerchainring. ( of course I also had to buy a road front derailleur, but now that I know that I don't use the inner chainring, I could have just run it without a front shifter/derailleur )

[motomech]

Nice build.
I use the Octalink version of that crank.
Not only was I able to get it with the 50T chain ring, but also it had an option for the short(165mm?)crank arms, which I needed because I went from 26" wheels to 24"s(yours look short to me, maybe an optical illusion). I was lucky with this set-up because after removing the frt. shifter/guide, the chain doesn't jump off when hitting bumps. The extra space on the handlebars is much appreciated.

SAM_0998.jpg (67.16 KiB) Viewed 4603 times

It is a 8 speed bike, and with most hub motors that is about the largest set of cogs even with spacers without over stretching the rear dropout/rear frame of a bike.

I think you are making a bigger deal of this than it is. Getting an extra milimeter or two does not require "Stretching". That implies deformation of the chainstays, which is not the case. I think spreading is the correct verb and I can do it with my bare hands.
I would suggest that you eventually you will want to install the Epoch DNP. Build quality takes a back-seat to the usefulness of the 11T sm. sprocket when it comes to getting the cadence down at 25 mph plus speeds.
Looking forward to the rest of the build info.

[ScooterMan101]

Just got back from my 7th ride on this , my first build.

Before the ride I said that I use the outer 50 tooth chainring 99% of the time , in fact the only time I remember shifting down to
the lower chainring was during the build/adjust process . That is until just an hour ago.

Well
I decided to really put this motor / bike / and me, to a real test today.
I went up a steep hill ( 2 Km exactly , that is 1.2 miles long ) , and looking down at the valley I
estimate the climb was apx. , 250-300 meters high , 750-900 elevation gain In just 2 K !

My down hill speed, not using the motor , just coasting , was 50 to 62 Kph !

I did finally use the inner chainring.
I am now glad that I bought the road derailleur and front shifter !

[ScooterMan101]

I am someone who uses all the gears on a bicycle, I live near hills , mountains really, they are only hills when I go only part the way up.
I do not have the strength in my legs that most people do. before today on small hills I used only 8 speeds, but today when I went up a very steep hill. I used all 16. when you get arthritis in your knees you will then understand. Talking to someone who does , not, have arthritis or weak Legs/ knees about this is frustrating, cause you just do not understand until you are in the same physical condition .

My crank arms are 175mm since this a motor bicycle I decided to use the longer crank arms, which is typical for a medium size bike anyway.

On a Road bike using just my legs I use a shorter length 172.5 for faster cadence .

I did , spread, the chainstays out even with just a 8 speed cog. using a 2mm washer from the hardware store. I did use a 2mm washer on the other side as well. so now my chainstays are 139 mm or more wide.

When are the Mgf"s of hub motors going to make them to not require so much dishing and design / make them to accept up to 11 speed cassettes ?

I was at another bike shop the other day , and they said that 9 and even 10 speed is being fazed out , 2016 will see even more 11 speed bikes ( 2 x 11 and 1 x 11 )
The makers of these hub motors , really do need to step up and make a better product !
Just because, You , perhaps do not use all the cogs, the fact is that most bikes these days have 9 , 10 , 11 speed cassettes.

>
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Nice build.
I use the Octalink version of that crank.
Not only was I able to get it with the 50T chain ring, but also it had an option for the short(210mm?)crank arms, which I needed because I went from 26" wheels to 24"s(yours look short to me, maybe an optical illusion). I was lucky with this set-up because after removing the frt. shifter/guide, the chain doesn't jump off when hitting bumps. The extra space on the handlebars is much appreciated.

SAM_0998.jpg

It is a 8 speed bike, and with most hub motors that is about the largest set of cogs even with spacers without over stretching the rear dropout/rear frame of a bike.

I think you are making a bigger deal of this than it is. Getting an extra milimeter or two does not require "Stretching". That implies deformation of the chainstays, which is not the case. I think spreading is the correct verb and I can do it with my bare hands.
I would suggest that you eventually you will want to install the Epoch DNP. Build quality takes a back-seat to the usefulness of the 11T sm. sprocket when it comes to getting the cadence down at 25 mph plus speeds.
Looking forward to the rest of the build info.

[ScooterMan101]

Besides this bike being my first electric conversion, I also decided to try to build up my own wheel for the first time . Thanks to E.S. there are threads , and links to wheel building.

First I looked at all the different size rims, I got the Hub Motor / Controller /Batteries before getting the bike, so I was not sure if it was going to go on a 26" wheel bike, or a 700c wheel bike or a 27.5" wheel bike. I decided on a 27.5 because it seems that it is going to be the norm for Medium / Medium Large , and even some Large size bike frames in the future, in fact at bike stores even this year the wheel size you get on your new bike is a different size depending on the frame size you are getting.
But more than that I decided to try a 27.5 inch wheeled bike because if I do want to transfer the hub wheel build to a different bike, Like a 29 er frame bike, or sturdy frame Gravel 700c or Cyclocross 700c wheel bike.
With a wide/tall 27.5 inch tire you are almost at the same outer diameter as a skinny 700c tire. My 27.5 with 54mm wide tires are just 5-6mm
less outer diameter than a 700c x32mm wide tire wheel !

For the 27,5 wheel build I decided to buy the Mavic EN321 650b disc rim since this is a mountain bike that I want to take on the dirt in the future.

For the Spokes I bought the Sapim 14/15 Gauge double butted spokes with brass nipples.

Since this was my first wheel build , I decided to do a 2 cross pattern to make it more simple.
I did however have to take it to a local bike shop/mechanic to really dial in the Truing and get out the hop on the wheel .

My tires are the Continental Tour Ride tire. 54 mm wide. However if you only ride on the street you could go with the same tire in a 42mm wide .

[ScooterMan101]

Having bought a hard tail bike for the conversion , instead of a Full Suspension, It is a good idea to use a suspension seat post.

Had this been a road bike conversion, and, if the Specialized CGR ( Cobbler Gobbler ) seat post was priced better, I would have bought it.

So for a more affordable price I got the Cane Creek Thudbuster ST seat post. I had used the Thudbuster LT seat post on a Mountain Bike a few years back
and found it to be quite plush and it really saved my back hitting unexpected hard bumps while sitting. The Thudbuster ST is not as plush, it is made for the road, but it still comes in handy when needed.

One thing I did not find on E.S. was how people mounted a bottle cage when putting the batteries in the front frame triangle.
Having seen TT Riders and Tri Bike setups, I wondered why no one that posted their bike here on E.S. , was using what TT and Tri Bikes do, mount the bottle cage behind the seat.
I got the single bottle cage bracket to start of with , but I also have a double Made by Profile Design, just in case I want to go on longer rides in the future.

[ScooterMan101]

Not having done a electric conversion on a bike before, I was not sure on what motor to get.

The one recurring comment from the long term/experienced posters / builders on this form said that most all, if not all , of them started out with lower power units like 250-400 watt motors, but then went on to 500 watt to 1,000 watt size motors. Li-Poly or Li-Ion Batteries, Good Quality Controllers and the Cycle Analyst.

Also not having ordered from un-known vendors on the internet before, and not wanting to take a risk with hundreds of dollars, I decided to call a business that I had bought a scooter from before.
I had even gone to their warehouse in the past, and seen the other electric conversion projects that they had done like motorcycles , kits for boats, saw some bench testing/projects. So I knew that I was safe in getting a good product and I could even pick up what I need in Person, since I live less than 2 hours away. That place is electricmotorsports.com located in Oakland.

I decided to just get what they had in stock in a hub bicycle motor.

I got lucky , Todd at Electric Motorsports in Oakland California had a number of Mac 500-1000 watt rear hub motors available, as well as a good Infineon Controller, and some Li-FePo4, Batteries ( at least I think that is their chemistry .
I bought both 36 volt as well as 48 volt batteries, as My scooter runs on 36 volts, and was not sure on 36 or 48 volt for the bicycle. Todd did not have the Cycle Analyst 2.3 in stock so he said to call Grin Technologies in Vancouver , BC Canada for it.
I wound up buying the Mac 6t rear hub motor, it takes a freewheel.
it is a " Fast Motor" meaning it is wound / made for a little less torque but a little more speed. that is OK with me since I am used to riding a Motorcycle, and even high powered e-bikes don't really seem all that high powered to me anyway .
with 7 rides on it now, I can say that I am very pleased with the performance, and that I chose to start off with a power level, that other experienced DIY e-bike enthusiasts go with .

If you do get a Mac Rear Hub Motor, there are a couple of things to look out for when building it up .
First if you go with more than a 7 speed freewheel, you will have to add a 2mm or more spacer on the freewheel side between the freewheel/axle and the Frame/dropouts . I went with a 8 speed freewheel and added a 2mm spacer on that side and the disc brake side as well. a 9 speed freewheel would need another 1-2mm as well as so If you go with a 9 speed freewheel count on using 3-4mm of spacing. So your dropout spacing will then be 139-143 mm. Go with a 8 speed and it will be 139mm.
Also
The bolts that you use to bolt on a disc rotor to the hub are longer than the 6 holes in the motor casing.
You, MUST , use a spacer /or washers to effectively shorten the length that those 6 rotor mounting bolts will then be screwed into the motor casing.
one way is to go to your hardware store and get many washers. like 3-4 for each bolt.
I found a better way to do it. I found an old disc brake rotor, then took out the grinder , grinded the outer part of the disc away to leave only the area around the 6 bolt holes. now I have a spacer that is thick enough to make the 6 rotor bolts the right enough length as to not go into the motor itself .

( Edit : a year after doing this in 2015 , EM3ev now sells the right thickness spacers to use on the Mac Motor )

Keeping those two considerations in mind , I can say that this is a good Hub Motor, it is powering me up hills / gradients that my legs just can not do. and I can run it at just a couple hundred of watts at 10-12 mph ( 17-20 Kph ) at 175-225 watts ! ( on Flat Level Road with No Wind ) , to really stretch out my range , OR , really get on the throttle to get better speed/steep hill climbing ability.

[ScooterMan101]

One more Item you must do with a 2013 Mac Hub Motor. ( on the new later model 2016 Mac's and newer, you could use a 180 mm disc )

A standard 160 mm Disc Rotor, and a 180 Disc Rotor will not work with most every disc brake caliper .

The housing of the Mac Hub gets in the way, the way to make the Mac Hub motor work with disc brakes is to get a 203mm Rotor and 203 , Mounting Adapter, also remember to use a home made spacer , inside or outside of the rotor so as to not tighten the rotor mounting bolts into the motor casing. ( see above picture ) .

[towodi63m]

Love the Thud Buster!!! Is it really as good as they say?

[ScooterMan101]

Yes the long travel version, the ST is not as good but better than the straight up and down cheep ones. I now have the LT version on that bike.